EdgePro Owners: Mirror finish advice

[Kyrs]

Hey guys,

I just got myself an Apex kit with all the trimmings, but I can't seem to get the mirror finish properly. I started with the 120 and worked every stone up until the 6000 grit polishing tape [15 degrees, FYI] I get a lot of mini scratches along the blade, and well, pics or it didn't happen:

Any help would be appreciated! Thanks in advance!

-K

 

[Jason B.]

Just from the pics,

That looks less than 15 per side

Use each grit longer, many of those scratches are likely 600 grit or less.

Work at setting the bevel more, I can see at the belly you did not apex the edge.

 

[williamsld8]

I'm going to go out on a limb here and give my thoughts: 1) Too much pressure while 2) not spending enough time on the in-between grits to refine the scratch pattern, leaving you with larger ones when you should have a mirror finish. Any more knowledgeable gents out there feel free to step in and correct me if I'm wrong.

 

[Kyrs]

Just from the pics,

That looks less than 15 per side

Thanks for your response. I set the marker at 15* (which I did verify in the book). I must be holding the knife lower then. When they say hold the knife on the Apex on the flat, are they referring to the ZT logo (pic 1), or just below the ZT logo?

Use each grit longer, many of those scratches are likely 600 grit or less.

Good point, but I thought I had spent enough. Guess I'll have to go back to the 120 just to be safe?

Work at setting the bevel more, I can see at the belly you did not apex the edge.

I'm not sure what you mean... do you mean I should steepen the angle more near the edge of the blade?

 

[Kyrs]

I'm going to go out on a limb here and give my thoughts: 1) Too much pressure while 2) not spending enough time on the in-between grits to refine the scratch pattern, leaving you with larger ones when you should have a mirror finish. Any more knowledgeable gents out there feel free to step in and correct me if I'm wrong.

Thanks for your input. I thought that might have been the case, but knifenut up there said the same... will look at it again.

 

[Jason B.]

If you look at the first pic you see what looks like a microbevel in the belly to tip section. "Not apexed" means you didn't grind the edge down far enough and sharpened slope "A" & "B" never met in the middle creating a sharp apex.

 

[Jason B.]

I align a bevel to the center of a blade so I would place the knife on the ZT logo so you had 15 per side in relation to the blade thickness not the grind.

 

[williamsld8]

If you look at the first pic you see what looks like a microbevel in the belly to tip section. "Not apexed" means you didn't grind the edge down far enough and sharpened slope "A" & "B" never met in the middle creating a sharp apex.

I see it too, pretty much starts where the belly itself begins, under the mass of deeper scratches.

 

[jsp]

Could it be that the polishing tape was not applied evenly on the aluminum blank causing the scratches?

 

[Jason B.]

Could it be that the polishing tape was not applied evenly on the aluminum blank causing the scratches?

No, the size of scratches indicate it was a previous stone. Also the polish is a surface polish, if it was created by the tapes the scratches would be more pronounced and the "background" would have a higher level of finish closer to the final 6k level.

 

[Noctis3880]

Thanks for your response. I set the marker at 15* (which I did verify in the book). I must be holding the knife lower then. When they say hold the knife on the Apex on the flat, are they referring to the ZT logo (pic 1), or just below the ZT logo?

You have to consider that the largest flat surface on the 0350 isn't perpendicular(it has an angle or a slant). The 15 degree setting is 15 degrees relative to the table. Unless the blade is saber ground, the largest flat surface you rest the blade on will be at an angle, which means the actual angle is lower than what you set it at. One suggestion would be to rest the blade on a surface that's parallel to the table(exactly where the ZT logo is on the blade) and grind at that angle you want for a bit, then mark the ground area with a sharpie, rest the blade back on the largest flat surface(below the ZT logo), and adjust the angle until you can remove the mark with one light swipe.

To be honest though, I don't think you picked the best knife for the Edge Pro Apex. The blade is also a recurve, so without the 1/2" stones you might not be fully sharpening the inside of the recurve.

 

[Skimo]

Noctis hit it spot on, it's definitely lower than 15° per side because you laid it on the flats.

1. form burr at 120.
2. remover burr.

3. perform step 1 and 2 with each advancing grit 220-320-600 etc.
4. between each step check for scratch pattern.


That edge isn't even mostly 600, that's a lot of 320 grit there, but what it looks like is you need to hit the 120 grit stone and take your time moving up through the grits.

 

[Ben Dover]

Noctis hit it spot on, it's definitely lower than 15° per side because you laid it on the flats.

1. form burr at 120.
2. remover burr.

3. perform step 1 and 2 with each advancing grit 220-320-600 etc.
4. between each step check for scratch pattern.


That edge isn't even mostly 600, that's a lot of 320 grit there, but what it looks like is you need to hit the 120 grit stone and take your time moving up through the grits.

I must say that the most dificult part of the learning curve on any Edge-Pro, for me at least, was acquiring the patience to assure that each stone completely removed the larger scratches from the previous stone before advancing to higher grits.

I found that an excellent tool for learning was a relatively flat blade, like a butcher knife, of fairly mild steel, that cut quickly and easily. Once I had experienced an edge that completely met my expectations, I felt more confident in tackling better steels and different grinds, and I somewhat miraculously began to acquire the considerable patience necessary to deal with them.

 

[Holmesmade]

Keeping the stones wet helps them cut faster by floating the crud away from the stones and the blade, but if you let a bit of slurry build up it can help polish out more of each grit size's scratches. Just be sure to wipe away all the crud from the blade between stone changes and rinse the stones well before you start each new blade.

Use less pressure as you work. Let the stones do everything for you so you're not cutting unevenly or getting coarser scratches than needed.

A hard leather strop with a fine polishing compound will help eliminate those last few scratches.

 

[Kyrs]

Thanks for your help guys!

 

[Kyrs]

Just a small update:

I blew up the angle at the very last second, but it personally doesn't matter to me - I'm going to be using this as my hard use work knife, so I'll be sharpening it again shortly.

Thanks again for all the help, and going slow made a huge difference!